Microcatheter System

ABSTRACT

A microcatheter system is disclosed which may include a microcatheter, one or more microcatheter extensions, and/or a microcatheter hub. In an embodiment, the microcatheter has a plurality of zones where the outside diameter of each zone from the distal to the proximal end has an outside diameter that is the same as or greater than the previous zone while the inside diameter is constant throughout the microcatheter length. In a further embodiment, a unique joining mechanism is employed for coupling a microcatheter to a microcatheter extension or to a microcatheter hub.

RELATED APPLICATION

The present application claims priority benefit of U.S. ProvisionalApplication No. 62/159,543, filed 11 May 2015 and entitled“Microcatheter System”, the entirety of which is hereby incorporatedherein by reference.

FIELD

This disclosure relates to a microcatheter system, including a systemhaving a microcatheter and a microcatheter extension and/or amicrocatheter hub, where a unique joining mechanism couples two of thecomponents together.

BACKGROUND

Microcatheters, including endovascular and neuroendovascularmicrocatheters, are generally microtubes inserted into the body througha blood vessel such as the femoral artery and have a variety of uses.Typically, microcatheters have a distal and a proximal end, where at orclose to the distal end a marker band is employed for visualization ofmicrocatheter positioning during in vivo use. The marker band typicallycomprises a metal or metal alloy ring such as platinum, nitinol and/orgold rings which can be visualized via fluoroscopy.

Microcatheters are typically used to embolize the neurovasculature suchas in treating arteriovenous malformations (AVMs), aneurysms, and thelike in a relatively non-invasive manner. Microcatheters with sufficientflexibility and size for applications in small tortuous vessels havebeen developed but typically require the continuous use of a guidecatheter.

A wide variety of commercially available microcatheters have beendeveloped for insertion in the vascular system for a number ofdiagnostic or therapeutic applications. Certain applications, however,require a small diameter and very flexible catheter to access smalltortuous vessels in situ. Guide catheters of larger diameter are usuallyemployed to act as a conduit to help support microcatheter access. Oneproblem associated with the removal of guide catheters is the increasedrisk associated with thromboembolic and vascular wall injurycomplications. It would be beneficial to have a microcatheter systemthat can remain in situ at a desired vascular location without the needfor a larger diameter guide catheter to also remain in situ.

SUMMARY

An aspect of at least one of the embodiments described herein includesthe realization that it is advantageous to provide microcatheters whichcan remain in situ at a desired vascular location without the need for alarger diameter guide catheter to also remain in situ. It is furtheradvantageous to provide microcatheters which easily are extensible andsafely detachable/attachable in situ microcatheters with a uniquejoining mechanism which couples, for example, a microcatheter with amicrocatheter extension without requiring an increase in the diameter ofthe microcatheter system at the joint. The unique joining mechanism issometimes referred to herein as an internal Luer lock mechanism. Thematching parts (male (probe) and female (receptacle) portions asdescribed in further detail below) of the unique joining mechanism maybe secured together by, for example, press fitting so that the matchingparts remain in place due to friction.

According to one aspect of the present disclosure, a microcathetersystem is described which includes a microcatheter having a distal endand a proximal end, wherein an internal diameter is constant throughout,and wherein the microcatheter includes a plurality of zones each zonehaving an outside diameter that is different from the outside diameterof each of the other zones in the plurality of zones; wherein theproximal end of the microcatheter is configured as a first receptaclefor receiving a first probe for connecting a first microcatheterextension or a microcatheter hub to the microcatheter, and wherein anoutside diameter of the first receptacle is no greater than a largestdiameter of the zones in the plurality of zones; and the firstmicrocatheter extension having a distal end and a proximal end, whereinan internal diameter is constant throughout, and wherein an outsidediameter is constant throughout, and wherein the distal end of the firstmicrocatheter extension is configured as the first probe to be receivedby the first receptacle of the proximal end of the microcatheter, andwherein an outside diameter of the first probe is less than an internaldiameter of the first receptacle, wherein the internal diameter of themicrocatheter is the same as the internal diameter of the firstmicrocatheter extension, and wherein an outside diameter of the firstmicrocatheter extension is the same as the outside diameter of thelargest diameter of the zones in the plurality of zones.

According to another aspect of the present disclosure, a microcathetersystem is described which includes a microcatheter having a distal endand a proximal end, wherein an internal diameter is constant throughout,and wherein the microcatheter includes a plurality of zones each zonehaving an outside diameter that is different from the outside diameterof each of the other zones in the plurality of zones; wherein theproximal end of the microcatheter is configured as a first probe forconnecting to a first receptacle for connecting a first microcatheterextension or a microcatheter hub to the microcatheter, and wherein anoutside diameter of the first probe is less than an internal diameter ofthe first receptacle; and the first microcatheter extension having adistal end and a proximal end, wherein an internal diameter is constantthroughout, and wherein an outside diameter is constant throughout, andwherein the distal end of the first microcatheter extension isconfigured as the first receptacle to receive the first probe of theproximal end of the microcatheter, and wherein an outside diameter ofthe first receptacle is no greater than a largest diameter of the zonesin the plurality of zones, wherein the internal diameter of themicrocatheter is the same as the internal diameter of the firstmicrocatheter extension, and wherein an outside diameter of the firstmicrocatheter extension is the same as the outside diameter of thelargest diameter of the zones in the plurality of zones.

Numerous other advantages and features of the present disclosure willbecome readily apparent from the following detailed description, theaccompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is best understood from the following detaileddescription when read in conjunction with the accompanying drawings. Itis emphasized that, according to common practice, the various featuresof the drawings are not necessarily to scale. On the contrary, thedimensions of the various features are arbitrarily expanded or reducedfor clarity. Like reference numerals denote like features throughoutspecification and drawings.

FIG. 1 is a schematic illustration of a microcatheter in accordance withone embodiment.

FIG. 2 is a schematic illustration of a microcatheter extension inaccordance with one embodiment.

FIG. 3 is a schematic illustration of the connection between amicrocatheter and a microcatheter extension in accordance with oneembodiment.

FIG. 4 is a schematic illustration of a connection between amicrocatheter and a microcatheter hub, or the connection between amicrocatheter extension and a microcatheter hub in accordance with oneembodiment.

DETAILED DESCRIPTION

This description of the exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. In the description, relativeterms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,”“below,” “up,” “down,” “top” and “bottom” as well as derivative thereof(e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should beconstrued to refer to the orientation as then described or as shown inthe drawing under discussion. These relative terms are for convenienceof description and do not require that the apparatus be constructed oroperated in a particular orientation. Terms concerning attachments,coupling and the like, such as “connected” and “interconnected,” referto a relationship wherein structures are secured or attached to oneanother either directly or indirectly through intervening structures, aswell as both movable or rigid attachments or relationships, unlessexpressly described otherwise.

FIG. 1 illustrates a notional schematic of a microcatheter according toan embodiment of the present disclosure. The microcatheter 100 isdesigned along standard neuroendovascular microcatheter platforms with agenerally tubular body to allow for the delivery of, e.g., detachablecoil systems, particulate matter injections, as well as liquid injectionand infusions in either a transient and/or in situ continuous manner.The microcatheter 100 has a distal end 110, which is also marked as A, aproximal end 150, which is also marked as E, and a transition portion.The transition portion of the microcatheter 100 includes four distinctzones from 110 to 120 is zone AB, from 120 to 130 is zone BC, from 130to 140 is zone CD, and from 140 to 150 is zone DE. In one embodiment,zone AB and zone BC are usually disposed inside a body, while zone CDand zone DE are usually disposed outside the body.

In an embodiment, the tubular body of the microcatheter 100 has anincreasing outer diameter (“OD”) in the direction from the distal end tothe proximal end. For example, the outer diameter of zone AB is nogreater than the outer diameter of zone BC, the outer diameter of zoneBC is no greater than the outer diameter of zone CD, the outer diameterof zone CD is no greater than the outer diameter of zone DE.

In another embodiment, more than four zones are employed. In anotherembodiment, fewer than four zones are employed. In another embodiment,more than two zones are placed inside the body. In yet anotherembodiment, fewer than two zones are placed inside the body.

In one embodiment, the transition in outer diameter between any twoabutting zones is a step change. In another embodiment, the transitionin outer diameter between any two abutting zones is a gradual change. Inanother embodiment, the transition in outer diameter between any twoabutting zones is a taper change. In another embodiment, the transitionin outer diameter between any two abutting zones is a chamfer change. Inanother embodiment, the transition in outer diameter between any twoabutting zones is a fillet change. One of skill in the art will readilyunderstand that the current disclosure encompasses situations where morethan one type of transition occurs along the length of a microcathetersuch as, for a non-limiting example, a step change occurs between afirst two abutting zones and a tapering change occurs between a secondtwo abutting zones.

One advantage of the microcatheter described herein is that thesubstantially increased proximal outer diameter of the microcatheter andmicrocatheter extension increases the stability of the overallmicrocatheter system.

In one embodiment, the overall length of the microcatheter 100 is 150 cmand may optionally include one or two distal radio-opaque markers forvisualization with detachable coil deployment. In one embodiment, themicrocatheter 100 employs a nitinol braiding system throughout theentire length which enables improved stability. In one embodiment, theinner diameter of the microcatheter 100 remains constant at 0.4138 mmthroughout the entire length of the microcatheter 100. In anotherembodiment, the inner diameter of the microcatheter 100 remains constantat approximately 0.4 mm.

In one embodiment, zone AB is 30 cm in length and 0.57 mm in outerdiameter (or 1.7 Fr); zone BC is 15 cm in length, and 0.73 mm (or 2.2Fr) in outer diameter; zone CD is 15 cm in length, and 1.17 mm (or 3.5Fr) in outer diameter; zone DE is 90 cm in length, and 1.33 mm (or 4 Fr)in outer diameter.

As would be apparent to one of ordinary skill in the art, the exemplarylength or lengths listed above for any one or more zone may be differentwithout departing from the spirit and intent of the present disclosure.Similarly, the exemplary inner diameter may be different withoutdeparting from the spirit and intent of the present disclosure.Likewise, the exemplary outer diameters listed above for any one or morezone may be different without departing from the spirit and intent ofthe present disclosure.

In one embodiment, the proximal end 150 (E) of the microcatheter 100contains a female portion of a unique joining mechanism (e.g., femaleinternal Luer lock mechanism) by which either the microcatheterextension 200 in FIG. 2 or FIG. 3 or the detachable/attachablemicrocatheter hub 400 in FIG. 4 may be attached and/or detached. Thisunique design allows the microcatheter 100 to be utilized as a standardmicrocatheter or as an exchange length microcatheter. In anotherembodiment, the proximal end 150 (E) of the microcatheter 100 contains aunique male portion of the unique joining mechanism (e.g., male internalLuer lock mechanism) by which either the microcatheter extension 200 orthe detachable/attachable microcatheter hub 400, each having a uniquefemale internal Luer lock mechanism, may be attached and/or detached.The internal Luer lock mechanism allows the microcatheter extension 200to be coupled to the microcatheter 100 in such a manner as to allow thesafe and effective removal of commonly employed guide catheter from theparent artery, allowing for continued treatment through themicrocatheter 100 for a prolonged manner and decreasing the riskassociated with thromboembolic complications.

FIG. 2 illustrates a notional schematic of a microcatheter extension 200according to an embodiment of the present disclosure. In an embodiment,this microcatheter extension 200 is similar in material andconfiguration in terms of inner diameter and outer diameter as zone DEof the microcatheter 100 shown in FIG. 1. In one embodiment, the overalllength of the microcatheter extension 200 from 210 to 220, or A′E′ is150 cm, the inner diameter 213 throughout remains the same as the innerdiameter of the microcatheter 100, which, in an embodiment, may be0.4138 mm, and the outer diameter throughout remains the same as theouter diameter of zone DE, which is 1.33 mm. Other lengths and diametersof the microcatheter extension 200 are contemplated in keeping with theprinciples of the present disclosure.

FIG. 3 illustrates a notional schematic of the internal Luer lockmechanism connection 300 according to an embodiment of the presentdisclosure. In one embodiment, at the distal end 210 of themicrocatheter extension 200 (A′) is a unique male internal Luer lockmechanism 211 which allows for connection to the proximal end 150 ofeither the microcatheter 100 or another microcatheter extension 200. Atthe proximal end 150 of the microcatheter 100 is a unique femaleinternal Luer lock mechanism 151. At the proximal end 220 of themicrocatheter extension (E′) is a unique female internal Luer lockmechanism which is identical in design to the mechanism found at theproximal end 150 of the microcatheter 100 (as shown at E in FIG. 3).This allows for connection with either an additional microcatheterextension 200 or detachable/attachable microcatheter hub 400 (FIG. 4).Internal diameter 153 is constant as described above.

In an alternate embodiment, the respective male and female portions areswapped between the connecting components. For example, at the distalend of the microcatheter extension 210 (A′) is a unique female internalLuer Lock mechanism which allows for connection to the proximal end 150of either the microcatheter 100 or microcatheter extension 200. At theproximal end 220 of the microcatheter extension 200 (E′) is a uniquemale internal Luer lock mechanism which is identical in design to themechanism found at the proximal end 150 of the microcatheter 100.

One advantage of the microcatheters described herein is that the uniqueLuer lock mechanism permits attachment and detachment of themicrocatheter extension in tandem and/or with a microcatheter hub.Effectively creating an extended microcatheter with a detachable hubpermits the safe and effective removal of a standard guiding catheter instandard exchange technique. This also allows the microcatheterdescribed herein to be used as a standard endovascular/neuroendovascularmicrocatheter for standard, commonly employed procedures as well asincreased utility when coupled with other components of the system.

FIG. 4 illustrates a notional schematic of the internal Luer lockconnection between a microcatheter 100, or a microcatheter extension200, and a microcatheter hub 400 having a distal end 410 and a proximalend 420, according to an embodiment of the present disclosure. In anembodiment, the microcatheter hub 400 is similar in design andcomposition to the standard endovascular microcatheter proximal aspect;a standard female Luer lock mechanism permits connection with standardLuer lock syringes, connectors, and intravenous tubing. In anembodiment, the detachable/attachable microcatheter hub 400 distalaspect 411 is unique in that it possess a unique male internal Luer locksystem which permits connection to either the proximal aspect 151 ofeither the microcatheter 100 or microcatheter extension 200. Theproximal end 420 of the microcatheter hub 400 is designed on a similarplatform to the standard microcatheter hubs, e.g., having a standardLuer lock receptacle 421, which allows for connection with standard Luerlock syringes, additional adapters such as three-way connectors androtating hemostatic valves, as well as intravenous tubing to permitpassage of detachable coil systems, particular matter, continuous liquidinfusions, as well as syringe injections. Internal diameter 412 may beconstant throughout as described above.

In another embodiment, the detachable/attachable microcatheter hub 400distal aspect is unique in that it possess a unique female internal Luerlock system which permits connection to either the proximal aspect 150of either the microcatheter 100 or microcatheter extension 200. Theability to attach or detach the detachable/attachable microcatheter hub400 permits the use of the microcatheter 100 as either a standardendovascular, or neuroendovascular microcatheter and/or as an exchangelength microcatheter. The detachable/attachable microcatheter hub 400 iscompatible with Dimethyl-Sulfoxide, and possess a pressure ratingidentical to the standard endovascular or neuroendovascularmicrocatheters.

One advantage of the microcatheters described herein is the improvedperformance of the microcatheters and increased safety with the exchangetechnique.

Although the subject matter has been described in terms of exemplaryembodiments, it is not limited thereto. Rather, the appended claimsshould be construed broadly, to include other variants and embodiments,which may be made by those skilled in the art.

What is claimed is:
 1. A microcatheter system comprising: amicrocatheter having a distal end and a proximal end, wherein aninternal diameter is constant throughout, and wherein the microcatheterincludes a plurality of zones each zone having an outside diameter thatis different from the outside diameter of each of the other zones in theplurality of zones; wherein the proximal end of said microcatheter isconfigured as a first receptacle for receiving a first probe forconnecting a first microcatheter extension or a microcatheter hub tosaid microcatheter, and wherein an outside diameter of the firstreceptacle is no greater than a largest diameter of the zones in theplurality of zones; and said first microcatheter extension having adistal end and a proximal end, wherein an internal diameter is constantthroughout, and wherein an outside diameter is constant throughout, andwherein the distal end of said first microcatheter extension isconfigured as the first probe to be received by the first receptacle ofthe proximal end of said microcatheter, and wherein an outside diameterof the first probe is less than an internal diameter of the firstreceptacle, wherein the internal diameter of said microcatheter is thesame as the internal diameter of said first microcatheter extension, andwherein an outside diameter of said first microcatheter extension is thesame as the outside diameter of the largest diameter of the zones in theplurality of zones.
 2. The microcatheter system of claim 1 wherein theproximal end of said first microcatheter extension is configured as asecond receptacle for receiving a second probe for connecting a secondmicrocatheter extension or said microcatheter hub to said firstmicrocatheter extension, and wherein an outside diameter of the secondreceptacle is no greater than the outside diameter of said firstmicrocatheter extension.
 3. The microcatheter system of claim 2 furthercomprising said microcatheter hub having a distal end and a proximalend, wherein a portion of an internal diameter of said microcatheter hubis the same as the internal diameter of said first microcatheterextension, and wherein the distal end of said microcatheter hub isconfigured as the second probe to be received by the second receptacle,and wherein an outside diameter of the second probe is less than aninternal diameter of the second receptacle.
 4. The microcatheter systemof claim 3 wherein the proximal end of said microcatheter hub comprisesa Luer lock receptacle.
 5. The microcatheter system of claim 1 whereinsaid microcatheter comprises nitinol braiding.
 6. The microcathetersystem of claim 1 wherein said first microcatheter extension comprisesnitinol braiding.
 7. The microcatheter system of claim 1 wherein anumber of zones in the plurality of zones is four.
 8. The microcathetersystem of claim 7 wherein a length of a first zone is approximately 30cm, the length of a second zone is approximately 15 cm, the length of athird zone is approximately 15 cm, and the length of a fourth zone isapproximately 90 cm, and wherein the first zone is at the distal end ofsaid microcatheter and the fourth zone is at the proximal end of saidmicrocatheter.
 9. The microcatheter system of claim 8 wherein theinternal diameter is 0.4138 mm.
 10. The microcatheter system of claim 8wherein the internal diameter is approximately 0.4 mm.
 11. Themicrocatheter system of claim 9 wherein the outside diameter of thefirst zone is approximately 1.7 Fr, the outside diameter of the secondzone is approximately 2.2 Fr, the outside diameter of the third zone isapproximately 3.5 Fr, and the outside diameter of the fourth zone isapproximately 4 Fr, where Fr=3D where D is the outside diameter of saidmicrocatheter in mm.
 12. The microcatheter system of claim 11 wherein alength of said first microcatheter extension is approximately 150 cm.13. A microcatheter system comprising: a microcatheter having a distalend and a proximal end, wherein an internal diameter is constantthroughout, and wherein the microcatheter includes a plurality of zoneseach zone having an outside diameter that is different from the outsidediameter of each of the other zones in the plurality of zones; whereinthe proximal end of said microcatheter is configured as a first probefor connecting to a first receptacle for connecting a firstmicrocatheter extension or a microcatheter hub to said microcatheter,and wherein an outside diameter of the first probe is less than aninternal diameter of the first receptacle; and said first microcatheterextension having a distal end and a proximal end, wherein an internaldiameter is constant throughout, and wherein an outside diameter isconstant throughout, and wherein the distal end of said firstmicrocatheter extension is configured as the first receptacle to receivethe first probe of the proximal end of said microcatheter, and whereinan outside diameter of the first receptacle is no greater than a largestdiameter of the zones in the plurality of zones, wherein the internaldiameter of said microcatheter is the same as the internal diameter ofsaid first microcatheter extension, and wherein an outside diameter ofsaid first microcatheter extension is the same as the outside diameterof the largest diameter of the zones in the plurality of zones.
 14. Themicrocatheter system of claim 13 wherein the proximal end of said firstmicrocatheter extension is configured as a second probe for connectingto a second receptacle for connecting a second microcatheter extensionor said microcatheter hub to said first microcatheter extension, andwherein an outside diameter of the second probe is less than an internaldiameter of the second receptacle.
 15. The microcatheter system of claim14 further comprising said microcatheter hub having a distal end and aproximal end, wherein a portion of an internal diameter of saidmicrocatheter hub is the same as the internal diameter of said firstmicrocatheter extension, and wherein the distal end of saidmicrocatheter hub is configured as the second receptacle for connectingto the second probe, and wherein an outside diameter of the secondreceptacle is no greater than a largest diameter of the zones in theplurality of zones.
 16. The microcatheter system of claim 15 wherein theproximal end of said microcatheter hub comprises a Luer lock receptacle.17. The microcatheter system of claim 13 wherein said microcathetercomprises nitinol braiding.
 18. The microcatheter system of claim 13wherein said first microcatheter extension comprises nitinol braiding.19. The microcatheter system of claim 13 wherein a number of zones inthe plurality of zones is four.
 20. The microcatheter system of claim 19wherein a length of a first zone is approximately 30 cm, the length of asecond zone is approximately 15 cm, the length of a third zone isapproximately 15 cm, and the length of a fourth zone is approximately 90cm, and wherein the first zone is at the distal end of saidmicrocatheter and the fourth zone is at the proximal end of saidmicrocatheter.
 21. The microcatheter system of claim 20 wherein theinternal diameter is 0.4138 mm.
 22. The microcatheter system of claim 20wherein the internal diameter is approximately 0.4 mm.
 23. Themicrocatheter system of claim 21 wherein the outside diameter of thefirst zone is approximately 1.7 Fr, the outside diameter of the secondzone is approximately 2.2 Fr, the outside diameter of the third zone isapproximately 3.5 Fr, and the outside diameter of the fourth zone isapproximately 4 Fr, where Fr=3D where D is the outside diameter of saidmicrocatheter in mm.
 24. The microcatheter system of claim 23 wherein alength of said first microcatheter extension is approximately 150 cm.